1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
5 -- V X A D D R 2 L I N E --
9 -- Copyright (C) 2002-2003 Ada Core Technologies, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 2, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING. If not, write --
19 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
20 -- MA 02111-1307, USA. --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
25 ------------------------------------------------------------------------------
27 -- This program is meant to be used with vxworks to compute symbolic
28 -- backtraces on the host from non-symbolic backtraces obtained on the target.
30 -- The basic idea is to automate the computation of the necessary address
31 -- adjustments prior to calling addr2line when the application has only been
32 -- partially linked on the host.
34 -- Variants for various targets are supported, and the command line should
37 -- <target>-addr2line [-a <target_arch>] <exe_file> <ref_address>
38 -- <backtrace addresses>
42 -- selects the target architecture. In the absence of this parameter the
43 -- default variant is chosen based on the Detect_Arch result. Generally,
44 -- this parameter will only be used if vxaddr2line is recompiled manually.
45 -- Otherwise, the command name will always be of the form
46 -- <target>-vxaddr2line where there is no ambiguity on the target's
50 -- The name of the partially linked binary file for the application.
53 -- Runtime address (on the target) of a reference symbol you choose,
54 -- which name shall match the value of the Ref_Symbol variable declared
55 -- below. A symbol with a small offset from the beginning of the text
56 -- segment is better, so "adainit" is a good choice.
58 -- <backtrace addresses> :
59 -- The call chain addresses you obtained at run time on the target and
60 -- for which you want a symbolic association.
62 -- TO ADD A NEW ARCHITECTURE add an appropriate value to Architecture type
63 -- (in a format <host>_<target>), and then an appropriate value to Config_List
66 with Text_IO
; use Text_IO
;
67 with Ada
.Integer_Text_IO
; use Ada
.Integer_Text_IO
;
68 with Ada
.Command_Line
; use Ada
.Command_Line
;
69 with Ada
.Strings
.Fixed
; use Ada
.Strings
.Fixed
;
71 with GNAT
.OS_Lib
; use GNAT
.OS_Lib
;
72 with GNAT
.Directory_Operations
; use GNAT
.Directory_Operations
;
73 with GNAT
.Expect
; use GNAT
.Expect
;
74 with GNAT
.Regpat
; use GNAT
.Regpat
;
76 procedure VxAddr2Line
is
78 Ref_Symbol
: constant String := "adainit";
79 -- This is the name of the reference symbol which runtime address shall
80 -- be provided as the <ref_address> argument.
82 -- All supported architectures
89 type Arch_Record
is record
90 Addr2line_Binary
: String_Access
;
91 -- Name of the addr2line utility to use.
93 Nm_Binary
: String_Access
;
94 -- Name of the host nm utility, which will be used to find out the
95 -- offset of the reference symbol in the text segment of the partially
98 Addr_Digits_To_Skip
: Integer;
99 -- When addresses such as 0xfffffc0001dfed50 are provided, for instance
100 -- on ALPHA, indicate the number of leading digits that can be ignored,
101 -- which will avoid computational overflows. Typically only useful when
102 -- 64bit addresses are provided.
104 Bt_Offset_From_Call
: Integer;
105 -- Offset from a backtrace address to the address of the corresponding
106 -- call instruction. This should always be 0, except on platforms where
107 -- the backtrace addresses actually correspond to return and not call
108 -- points. In such cases, a negative value is most likely.
111 -- Configuration for each of the architectures
112 Arch_List
: array (Architecture
'Range) of Arch_Record
:=
114 (Addr2line_Binary
=> null,
116 Addr_Digits_To_Skip
=> 0,
117 Bt_Offset_From_Call
=> -4),
119 (Addr2line_Binary
=> null,
121 Addr_Digits_To_Skip
=> 0,
122 Bt_Offset_From_Call
=> -4),
124 (Addr2line_Binary
=> null,
126 Addr_Digits_To_Skip
=> 0,
127 Bt_Offset_From_Call
=> 0),
129 (Addr2line_Binary
=> null,
131 Addr_Digits_To_Skip
=> 8,
132 Bt_Offset_From_Call
=> 0)
135 -- Current architecture
136 Cur_Arch
: Architecture
;
138 -- State of architecture detection
139 Detect_Success
: Boolean := False;
141 -----------------------
142 -- Local subprograms --
143 -----------------------
145 procedure Error
(Msg
: String);
146 pragma No_Return
(Error
);
147 -- Prints the message and then terminates the program
150 -- Displays the short help message and then terminates the program
152 function Get_Reference_Offset
return Integer;
153 -- Computes the static offset of the reference symbol by calling nm
155 function Get_Value_From_Hex_Arg
(Arg
: Natural) return Integer;
156 -- Threats the argument number Arg as a C-style hexadecimal literal
157 -- and returns its integer value
159 function Hex_Image
(Value
: Integer) return String_Access
;
160 -- Returns access to a string that contains hexadecimal image of Value
162 -- Separate functions that provide build-time customization:
164 procedure Detect_Arch
;
165 -- Saves in Cur_Arch the current architecture, based on the name of
166 -- vxaddr2line instance and properties of the host. Detect_Success is False
167 -- if detection fails
173 procedure Detect_Arch
is
174 Name
: constant String := Base_Name
(Command_Name
);
175 Proc
: constant String :=
176 Name
(Name
'First .. Index
(Name
, "-") - 1);
177 Target
: constant String :=
178 Name
(Name
'First .. Index
(Name
, "vxaddr2line") - 1);
181 Detect_Success
:= False;
187 if Proc
= "alpha" then
188 Cur_Arch
:= DEC_ALPHA
;
190 -- Let's detect the host.
191 -- ??? A naive implementation that can't distinguish between Unixes
192 if Directory_Separator
= '/' then
193 Cur_Arch
:= Architecture
'Value ("solaris_" & Proc
);
195 Cur_Arch
:= Architecture
'Value ("windows_" & Proc
);
199 if Arch_List
(Cur_Arch
).Addr2line_Binary
= null then
200 Arch_List
(Cur_Arch
).Addr2line_Binary
:= new String'
201 (Target & "addr2line");
203 if Arch_List (Cur_Arch).Nm_Binary = null then
204 Arch_List (Cur_Arch).Nm_Binary := new String'
208 Detect_Success
:= True;
220 procedure Error
(Msg
: String) is
228 --------------------------
229 -- Get_Reference_Offset --
230 --------------------------
232 function Get_Reference_Offset
return Integer is
233 Nm_Cmd
: constant String_Access
:=
234 Locate_Exec_On_Path
(Arch_List
(Cur_Arch
).Nm_Binary
.all);
236 Nm_Args
: constant Argument_List
:=
238 new String'(Argument
(1)));
240 Forever
: aliased String := "^@@@@";
241 Reference
: aliased String := Ref_Symbol
& "\s+\S\s+([\da-fA-F]+)";
243 Pd
: Process_Descriptor
;
244 Result
: Expect_Match
;
247 -- If Nm is not found, abort
249 if Nm_Cmd
= null then
250 Error
("Couldn't find " & Arch_List
(Cur_Arch
).Nm_Binary
.all);
254 (Pd
, Nm_Cmd
.all, Nm_Args
, Buffer_Size
=> 0, Err_To_Out
=> True);
256 -- Expect a string containing the reference symbol
259 Regexp_Array
'(1 => Reference'Unchecked_Access),
262 -- If we are here, the pattern was matched successfully
265 Match_String : constant String := Expect_Out_Match (Pd);
266 Matches : Match_Array (0 .. 1);
270 Match (Reference, Match_String, Matches);
271 Value := Integer'Value
273 & Match_String (Matches (1).First .. Matches (1).Last) & "#");
275 -- Expect a string that will never be emitted, so that the
276 -- process can be correctly terminated (with Process_Died)
279 Regexp_Array'(1 => Forever
'Unchecked_Access),
287 -- We can not get here
292 when Invalid_Process
=>
293 Error
("Could not spawn a process " & Nm_Cmd
.all);
297 -- The process died without matching the reference symbol or the
298 -- format wasn't recognized.
300 Error
("Unexpected output from " & Nm_Cmd
.all);
301 end Get_Reference_Offset
;
303 ----------------------------
304 -- Get_Value_From_Hex_Arg --
305 ----------------------------
307 function Get_Value_From_Hex_Arg
(Arg
: Natural) return Integer is
308 Cur_Arg
: constant String := Argument
(Arg
);
312 -- Skip "0x" prefix if present
314 if Cur_Arg
'Length > 2 and then Cur_Arg
(1 .. 2) = "0x" then
320 -- Add architecture-specific offset
322 Offset
:= Offset
+ Arch_List
(Cur_Arch
).Addr_Digits_To_Skip
;
326 return Integer'Value ("16#" & Cur_Arg
(Offset
.. Cur_Arg
'Last) & "#");
327 end Get_Value_From_Hex_Arg
;
333 function Hex_Image
(Value
: Integer) return String_Access
is
334 Result
: String (1 .. 20);
338 Put
(Result
, Value
, 16);
339 Start_Pos
:= Index
(Result
, "16#") + 3;
340 return new String'(Result (Start_Pos .. Result'Last - 1));
349 Put_Line ("Usage : " & Base_Name (Command_Name)
351 & Ref_Symbol & " offset on target> <addr1> ...");
356 Ref_Static_Offset, Ref_Runtime_Address, Bt_Address : Integer;
358 Addr2line_Cmd : String_Access;
360 Addr2line_Args : Argument_List (1 .. 501);
361 -- We expect that there won't be more than 500 backtrace frames
363 Addr2line_Args_Count : Natural;
367 -- Start of processing for VxAddr2Line
373 -- There should be at least two arguments
375 if Argument_Count < 2 then
379 -- ??? HARD LIMIT! There should be at most 501 arguments
381 if Argument_Count > 501 then
382 Error ("Too many backtrace frames");
385 -- Do we have a valid architecture?
387 if not Detect_Success then
388 Put_Line ("Couldn't detect the architecture");
393 Locate_Exec_On_Path (Arch_List (Cur_Arch).Addr2line_Binary.all);
395 -- If Addr2line is not found, abort
397 if Addr2line_Cmd = null then
398 Error ("Couldn't find " & Arch_List (Cur_Arch).Addr2line_Binary.all);
401 -- The first argument specifies the image file. Check if it exists.
403 if not Is_Regular_File (Argument (1)) then
404 Error ("Couldn't find the executable " & Argument (1));
407 -- The second argument specifies the reference symbol runtime address.
408 -- Let's parse and store it
410 Ref_Runtime_Address := Get_Value_From_Hex_Arg (2);
412 -- Run nm command to get the reference symbol static offset
414 Ref_Static_Offset := Get_Reference_Offset;
416 -- Build addr2line parameters. First, the standard part
418 Addr2line_Args (1) := new String'("--exe=" & Argument
(1));
419 Addr2line_Args_Count
:= 1;
421 -- Now, append to this the adjusted backtraces in arguments 4 and further
423 for J
in 3 .. Argument_Count
loop
425 -- Basically, for each address in the runtime backtrace ...
427 -- o We compute its offset relatively to the runtime address of the
432 -- o We add this offset to the static one for the reference symbol in
433 -- the executable to find the executable offset corresponding to the
434 -- backtrace address.
436 Bt_Address
:= Get_Value_From_Hex_Arg
(J
);
439 Bt_Address
- Ref_Runtime_Address
441 + Arch_List
(Cur_Arch
).Bt_Offset_From_Call
;
443 Addr2line_Args_Count
:= Addr2line_Args_Count
+ 1;
444 Addr2line_Args
(Addr2line_Args_Count
) := Hex_Image
(Bt_Address
);
447 -- Run the resulting command
449 Spawn
(Addr2line_Cmd
.all,
450 Addr2line_Args
(1 .. Addr2line_Args_Count
), Success
);
455 -- Mask all exceptions